Boston University worked too hard down the stretch to earn the No. 2 seed in the Patriot League playoffs only to give it away in the quarterfinals.

The Terriers compiled a team effort in all categories to outlast No. 7 seed Navy 70-61 in a spirited round and tumble encounter on Thursday night under The Roof at Case Gym

The Terriers (16-16, 11-8) advanced to the Patriot League semifinals for the sixth time and will host No. 6 Lehigh on Sunday afternoon (4) at Case Gym. BU swept Lehigh in the regular season, but the two games were decided by three points.

“I looking forward to another war, an absolute war,” said BU coach Joe Jones, who is in his 13th season. “They will be ready, they have talent, and they have arguably two of the best guards.

“We will have our hands full and it will be a great contest and a great semifinal game.”

Anthony Morales led a balanced BU attack with 17 points while the team accounted for 39 rebound, 15 assists and 32 bench points. Dynamic point guard Austin Benigni led Navy with 22 points, 10 from the free throw line. BC limited Navy to 4-of-24 from behind the arc while making seven.

“I thought that this was one of our most balanced games in terms of contributions we got down the line from all the guys,” said Jones.

BU crashed the PL tournament riding a five-game win streak for the first time since 2011 when, as a No. 2 seed, it went on to capture the America East title. One of the five victories was a 75-64 win over Navy at home on Feb. 17. But the Midshipmen had also won five straight matches since that included a 64-48 trouncing of Maryland Loyola in a tournament play-in game on Tuesday.

“The younger guys know that now they belong, especially after we won five straight games,” said Morales, a senior forward from Boston. “For a young player that is very fulfilling. But me and Miles (Brewster) enforced to the guys we are the two seed but the two seed don’t get you an automatic win even at home.”

Both teams scored on their opening possessions, but the gunners fell silent over a four-minute stretch with BU going 1-8 and Navy 1-7 from the floor. The score was tied 2-2 at the first media timeout.

BU emerged from the break and went on a 14-4 run to go up 16-6 with 10:53 to play in the half. Morales and Brewster were good from downtown and Landrum closed the surge with a layup off the glass.

Benigni and Jordan Pennick got the stagnant Midshipmen moving, but BU countered every surge to go up 27-17 into the third media timeout. Brewster went showtime during the run with a rambunctious jam off a turnover and a falling down 3-point shot from the top of the key. Navy outscored BU 10-6 down the stretch to cut the Terriers’ lead to 33-27 at the break.

“They went on a hot streak, we went on hot streak but we clearly picked up our defense,” said Morales. “At the end of the day it was two teams that had grown defensively, especially at the beginning of the game when you have all that energy.”

BU maintained its slim first half lead through the opening nine minutes of the second. Morales and Kyrone Alexander kept the BU machine operational while Navy’s Benigni and Mac MacDonald limited the damage. BU led 58-49 at the third media timeout.

BU went up 65-53 on two from the line by Brewster with 3:03 to play. Morales put it away with two free throws with 22.1 seconds to play.